The present invention relates to a remote control device, particulary for controlling electrical and electronic household appliances, which can provide special operating instructions for each appliance to be controlled by using exchangeable memory elements. The remote control device is provided with keys and associated electronic display elements. The respective functions of the keys, as indicated by lettering or symbols displayed by the display elements, are controlled by digital circuitry or microprocessor according to the content of the exchangeable memory elements
Known remote control devices are dedicated to the control of particular appliances, and the number of keys and legends for the keys are exclusively devoted to the control of the predetermined appliances. In such a remote control device with predetermined key functions and impressed lettering, substantial problems are inevitable if a rather complex appliance, for example a video recorder, is to be controlled or if a number of different appliances are to be controlled. The number of keys required is then usually so large that a convenient size for the remote control device can be attained only by giving keys multiple uses. However, this multiple key use makes it necessary to accommodate many keys having multiple imprinted or engraved legends in a small area, so that it is extremely difficult for the user to operate rhe remote control device.
Moreover, the known remote control devices mostly require that the user observe an indicator unit at the appliance to be operated during the use of the remote control device. Often, the user can detect only by observation of the reaction of the appliance being controlled that the depression of a key in the remote control device has indeed triggered the desired reaction in the appliance being controlled. Particularly when entering a time, for example when setting an electronic clock module in the appliance being controlled or entering switching times, it is frequently necessary to perform cyclic function advances (i.e. forward and backward switching controlled by the actuation of a key), which is impossible as a practical matter without observing the display at the appliance being controlled. However, the necessity of having to observe the remote controlled appliance, which is usually disposed at a distance, is inconsistent with the very idea of remote control and considerably reduces the utility of a remote control device.